Vandenberghe R, Gitelman D R, Parrish T B, Mesulam M M
Cognitive Neurology and Alzheimer's Disease Center, Northwestern University Medical School, Chicago, Illinois, USA.
Neuroimage. 2001 Jul;14(1 Pt 1):37-47. doi: 10.1006/nimg.2001.0790.
Using event-related fMRI we determined the differential effects of feature- versus location-based cues for directing peripheral attention. Pairs of same-color targets appeared on the left and on the right. A predictive cue indicated whether the subsequent targeting of attention would be based on location (left versus right) or color (red versus blue). Subjects had to press a button when the relevant pair of targets (in the cued side of space or of the cued color) were identical in shape. The feature-based cue thus also led to a "global" expectancy of targets on either side of space whereas the location-based cue elicited a more "focal" expectancy limited to one side of space. The right inferior parietal lobule was more active when attention was targeted on the basis of location than of color. There was no difference between left-sided or right-sided attention in this region, indicating that it mediated the targeting to both sides of space. These results show that the right inferior parietal cortex plays a relatively selective role in mediating location-based and spatially focal modes of attentional deployment. Its relatively equal activation for leftward and rightward attentional shifts is also consistent with models of right hemispheric dominance of spatial attention.
我们使用事件相关功能磁共振成像技术，确定了基于特征与基于位置的线索在引导外周注意力方面的差异效应。一对相同颜色的目标出现在左侧和右侧。一个预测线索表明随后的注意力定向是基于位置（左对右）还是颜色（红对蓝）。当相关的一对目标（在空间的线索侧或线索颜色）形状相同时，受试者必须按下按钮。因此，基于特征的线索也导致对空间两侧目标的“全局”预期，而基于位置的线索引发的预期则更“集中”，仅限于空间的一侧。当注意力基于位置而非颜色进行定向时，右侧顶下小叶更为活跃。在该区域，左侧或右侧注意力之间没有差异，表明它介导了对空间两侧的定向。这些结果表明，右侧顶下皮质在介导基于位置和空间集中的注意力部署模式中发挥了相对选择性的作用。其对向左和向右注意力转移的相对同等激活也与空间注意力右半球优势模型一致。
